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Dietary supplement

L-Theanine 150 mg Ingredients & Drug Interactions

by BIOVEA

Capsule Category: Non-nutrient/non-botanical
Most serious interaction: Moderate
The interaction bottom line Most serious interaction: Moderate

L-Theanine 150 mg is a dietary supplement by BIOVEA with 1 active ingredient. Its ingredients are commonly taken for anxiety and stress, relaxation and calm, sleep support.Based on those ingredients, 565 medications have a known interaction with it, the most serious rated moderate. The ingredients most likely to interact are L-Theanine. Use the checker below to test your specific medication, or read the full HelloPharmacist Interaction Report.

HelloPharmacist Scorecard of L-Theanine 150 mg by BIOVEA

Our pharmacy team’s full take, with four database checks built into the cards below — a summary of what is known, not a grade of the product itself.

From our pharmacy team — supplement deep dive

What’s inside

Full disclosure
Ingredient Transparency · database check
Full

Every active ingredient lists its own amount on the label.

Why this rating?
  • The label discloses an exact amount for 1 of its 1 active ingredient.
  • No proprietary blends here — you can verify the dose of every single component.

This product contains one active ingredient: L-theanine, an amino acid derived from tea leaves. The capsule also contains inactive ingredients — rice flour, hydroxypropyl methylcellulose (a thickening agent), and vegetable magnesium stearate (a lubricant) — which are just there to hold the capsule together and help it dissolve.

Does it work?

Moderate evidence
Evidence for Intended Use · database check
By FDA rules, dietary supplements can’t claim to treat, cure, or prevent disease — so labels speak in careful marketing language. We discern each product’s intended use from its name, label claims, and label statements, then grade the clinical evidence for that use. How these ratings are computed

This product doesn't appear to be marketed for a specific use, so we graded Theanine's overall clinical evidence instead.

Moderate

Some clinical evidence supports Theanine for:

Why this rating?
  • We looked at the product name, claims, and label statements and couldn't find a stated purpose to grade.
  • Since the label doesn't commit to one use, we graded the ingredient's overall clinical evidence instead.
  • On file: Cognitive function — rated "Possibly Effective" (Natural Medicines).

The evidence for L-theanine is mixed. It's rated Possibly Effective for cognitive function, meaning some research supports it but the data isn't conclusive.

For age-related cognitive decline, Alzheimer's disease, generalized anxiety, OCD, and cancer, the evidence is Insufficient — we don't have reliable data to say whether it works for those uses. If you're considering this for a specific health goal, chat with your doctor about what the current science actually shows.

The evidence, ingredient by ingredient Theanine

How safe is it?

Well-documented data
Safety Information · database check
Well characterized

Adverse-effect, pregnancy, and general safety data are on file for most of these ingredients.

Why this rating?
  • We hold adverse-effect (side-effect) data for 1 of the 1 matched ingredient.
  • Pregnancy & breastfeeding safety ratings cover 1 of 1.
  • General safety write-ups exist for 1 of 1.
  • Remember: this measures how much safety information exists. Thin data is not the same as being safe.

L-Theanine is generally well tolerated in healthy adults for short-term use, but long-term safety hasn't been well studied, so we don't know what happens if you take it for months or years. The most common side effects are headaches, drowsiness, longer sleep, and more vivid dreams.

One pediatric case of facial tics was reported within days of starting a higher dose, though the child had a history of tics and they stopped when theanine was discontinued, so the link wasn't clear. There isn't enough safety data to recommend this during pregnancy or while breastfeeding — talk with your doctor or pharmacist about whether it's right for you in those situations.

Side effects, ingredient by ingredient Theanine

Meds to double-check

Moderate interaction found
Known Interaction Concern · database check
Moderate identified

The most serious documented interaction for these ingredients is Moderate. Check your medications for a personalized result.

Why this rating?
  • 1 of the 1 matched ingredient can interact with medications — Theanine.
  • The most serious interaction on file is rated Moderate.
  • For scale: 565 individual medications appear in the full list. A big number alone doesn't make a product dangerous — what matters is whether YOUR medication is on it, so run yours through the interaction checker on this page.

Check your blood pressure medications first — theanine can lower blood pressure on its own. Also confirm any CNS depressants (sleep aids, sedatives, anxiety medications) and serotonergic drugs (many antidepressants) with your doctor or pharmacist before starting.

Check your own medication Run your meds through the checker above

The bottom line

Scorecard at a glanceFully disclosed formula with some supporting evidence behind its ingredients' uses. Moderate medication interactions have been identified, and safety information is well characterized.

L-Theanine may help with focus and mental clarity, though the evidence is preliminary. If you take blood pressure medication or drugs that affect brain activity (like sleep aids or certain antidepressants), you'll want to check with your doctor or pharmacist before adding this.

It's generally well tolerated short-term, but long-term safety isn't established.

Educational only — not medical advice; always confirm with your pharmacist. Our editorial policy · How we use AI

Assessment coverage: 1 of 1 active ingredient matched to our full ingredient reviews (monographs). Based on the product label dated May 22, 2021.

This Scorecard evaluates available label information, ingredient evidence, and known medication-safety considerations. It does not independently verify product identity, purity, potency, contamination, or manufacturing quality. How these ratings are computed

At a glance

General information

Key facts about L-Theanine 150 mg, straight from the product label.

Brand BIOVEA
Barcode (UPC) 818423022871
Net contents 60 Vegetarian Capsule(s)
Market status On market
Date entered into DSLD May 22, 2021
DSLD ID 248966
Product type Non-nutrient/non-botanical
Supplement form Capsule
Dietary claims / uses All Other, Structure/Function
Intended target group(s) Vegan, Vegetarian, Adult (18 - 50 Years), Gluten Free
From the label
Everything in this section is reproduced from the manufacturer’s own product label — it’s the label speaking, not HelloPharmacist. We show it so you can see exactly what the maker states; we don’t verify or endorse those statements.

Supplement Facts

The label details for L-Theanine 150 mg by BIOVEA, sourced from the NIH Dietary Supplement Label Database.

Supplement Facts

Daily Value (DV) Target Group(s):
Adults and children 4 or more years of age
Minimum serving Sizes:
1 Vegetarian Capsule(s)
Maximum serving Sizes:
1 Vegetarian Capsule(s)
Servings per container
60
UPC/BARCODE
818423022871
IngredientAmount% DV
L-Theanine150 mg--

Other ingredients: Rice Flour, Hydroxypropyl Methylcellulose, Vegetable Magnesium Stearate

Tap any ingredient to jump to its full detail below.

Label statements
These statements are the manufacturer’s wording, reproduced from the product label — the label is saying it, not HelloPharmacist. We don’t verify or endorse them.
Seals/Symbols

GMP Compliant

Formulation

VG Vegan

Gluten free

Non-GMO

Premium quality guaranteed since 2001. BIOVEA is committed to product quality to support you and your family's wellness goals. Because we feel so strongly about the quality, potency and purity of our products, we 100% guarantee your satisfaction with every purchase.

Suggested/Recommended/Usage/Directions

Suggested Daily Intake: Take 1 capsule daily or every 8 hours as needed.

Precautions

Warning: If you are pregnant or lactating, consult a healthcare professional before using this product.

Keep out of reach of children.

Do not use this product if the safety seal on the bottle is broken.

Storage

Store in a cool, dry place.

General Statements

Guaranteed premium quality

Relaxation

FDA Statement of Identity

Dietary Supplement

FDA Disclaimer Statement

This statement has not been evaluated by the Food and Drug Administration. This product is not intended to diagnose, treat, cure, or prevent any disease.

See for yourself

L-Theanine 150 mg by BIOVEA label

The label scan from the NIH Dietary Supplement Label Database. Tap to enlarge.

What’s inside

The Ingredients in L-Theanine 150 mg by BIOVEA

This is the 1 active ingredient this product is made of. Select it to open its full monograph.

Serving size1 Vegetarian Capsule(s) Dosage formCapsule Servings per container60 Amounts shown are per serving.

L-Theanine

Interacts with
565 drugs
150 mg per serving

Theanine (usually L-theanine) is an amino acid found naturally in tea leaves that many people take to feel calmer and less stressed without strong dro...

L-Theanine monograph & interactions

Other (inactive) ingredients: Rice Flour, Hydroxypropyl Methylcellulose, Vegetable Magnesium Stearate. These complete the product’s ingredient list but are not active constituents.

Interaction report

L-Theanine 150 mg by BIOVEA Drug Interactions

Want to check YOUR meds against L-Theanine 150 mg?

Ask about interactions with your drugs in plain English — “Can I take it with lisinopril?” — and we find you the answer in seconds, ingredient by ingredient.

Go to the checker
565Drugs
172 Moderate 393 Minor

Ingredients driving the most interactions

Each ingredient & the kinds of drugs it affects

For each ingredient in L-Theanine 150 mg with known interactions, here are the types of medications it can affect. Open any type for the detail — or search your exact drug in the checker above.

L-Theanine3 drug types · 565 drugs

Antihypertensive Drugs

Theanine might lower blood pressure, potentiating the effects of antihypertensive drugs.
Animal research shows that theanine can lower blood pressure in spontaneously hypertensive animals. Theoretically, concomitant use of theanine and antihypertensive drugs might potentiate the antihypertensive activity.

Likelihood Possible Evidence D
Cns Depressants

Theoretically, theanine might have additive sedative effects when used in conjunction with CNS depressants. However, it is unclear if this concern is clinically relevant.
Theoretically, theanine may compete with glutamate and/or increase plasma gamma-aminobutyric acid (GABA) levels, which could cause CNS depression. In one clinical study, some subjects taking oral theanine reported drowsiness.

Likelihood Unlikely Evidence D
Serotonergic Drugs

Clinical studies regarding the effects of L-theanine on serotonin levels are conflicting. Some studies suggest it can increase serotonin levels in the brain while others report that it may decrease them. Nevertheless, there have been no reports of l-theanine being a causative agent in serotonergic-related side effects or serotonin syndrome.

Likelihood Unlikely Evidence C
The maker

Brand information

Manufacturer and brand details for L-Theanine 150 mg, from the product label.

BIOVEA

See all BIOVEA products
Name
BIOVEA
Street Address
9160 E. Bahia Dr.
City
Scottsdale
State
AZ
ZipCode
85260
Web Address
www.biovea.com
Pharmacist Counseling Corner

L-Theanine 150 mg by BIOVEA: Common Questions

Does L-Theanine 150 mg by BIOVEA interact with any medications?
Yes. Based on its ingredients, L-Theanine 150 mg has a known interaction with 565 medications. Use the checker to see how it interacts with a specific drug.
How can one product interact with so many drugs?
L-Theanine 150 mg contains a single active ingredient, and that one ingredient can interact with many different medications on its own. We check it against each medication and show the mechanism responsible.
Where does this information come from?
The product label data comes from the NIH Dietary Supplement Label Database (DSLD); the interaction data is built on the Natural Medicines database and reviewed by HelloPharmacist pharmacists.
What is L-theanine, and where does it come from?
L-theanine is an amino acid found naturally in tea leaves. It's the compound that gives tea some of its calming properties without the drowsiness of caffeine.
Will this help me focus or reduce anxiety?
L-theanine is Possibly Effective for cognitive function based on current research, but the evidence for anxiety disorders like GAD and OCD is Insufficient — we don't have enough reliable data to say it works for those. Ask your doctor if it might fit your situation.
What side effects should I watch for?
Headaches, drowsiness, longer sleep, and more vivid dreams are the main ones reported. They're usually mild, but if you notice anything unusual, stop and talk to your pharmacist.
Is it safe to take during pregnancy or while breastfeeding?
There isn't enough safety data to recommend it during pregnancy or breastfeeding. Talk with your doctor or pharmacist about your specific situation — they can help you decide what's right.
How long can I safely take this?
Short-term use in healthy adults is generally well tolerated, but long-term safety hasn't been well studied. If you're thinking of taking it for months, check with your pharmacist about what we know and don't know.

Written and reviewed by the HelloPharmacist editorial staff. Our editorial policy

Not sure if L-Theanine 150 mg is safe with your meds?

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Ask a pharmacist

Label information is sourced from the NIH Dietary Supplement Label Database and reflects the product version on file; always read your actual product label. This page is for education only and is not a substitute for professional medical advice. Confirm with your pharmacist or doctor before combining supplements and medications.

L-Theanine 150 mg label
Go deeper

The Full Monographs Behind L-Theanine 150 mg’s Ingredients

Every ingredient we hold a full HelloPharmacist monograph for — uses, evidence, safety, and the complete interaction list.

Sources

Sources & How We Checked

L-Theanine 150 mg's label data comes from the NIH Dietary Supplement Label Database; the ingredient interaction data is from the Natural Medicines database, reviewed by our pharmacists.

Content is written and reviewed by licensed HelloPharmacist pharmacists. See our data sources and editorial standards for how this information is built and checked.

The 6 references behind this product’s interaction data

Every citation that drives the interaction findings for this product’s ingredients, from the evidence-graded Natural Medicines (TRC Healthcare) database. Open an ingredient to browse its citations — links open the study on PubMed or the publisher’s site.

Theanine 6 references
  1. Yokogoshi H, Kobayashi M. Hypotensive effect of gamma-glutamylethylamide in spontaneously hypertensive rats. Life Sci 1998;62:1065-8.
  2. Haskell, C. F., Kennedy, D. O., Milne, A. L., Wesnes, K. A., and Scholey, A. B. The effects of L-theanine, caffeine and their combination on cognition and mood. Biol.Psychol. 2008;77(2):113-122. PubMed
  3. Yokogoshi, H., Kato, Y., Sagesaka, Y. M., Takihara-Matsuura, T., Kakuda, T., and Takeuchi, N. Reduction effect of theanine on blood pressure and brain 5-hydroxyindoles in spontaneously hypertensive rats. Biosci.Biotechnol.Biochem. 1995;59(4):615-618. PubMed
  4. Lyon MR, Kapoor MP, Juneja LR. The effects of L-theanine (Suntheanine®) on objective sleep quality in boys with attention deficit hyperactivity disorder (ADHD): a randomized, double-blind, placebo-controlled clinical trial. Altern Med Rev. 2011;16(4):348-
  5. Hidese S, Ota M, Wakabayashi C, et al. Effects of chronic l-theanine administration in patients with major depressive disorder: an open-label study. Acta Neuropsychiatr 2017;29(2):72-9.
  6. Tsuchiya T, Honda H, Oikawa M, et al. Oral administration of the amino acids cystine and theanine attenuates the adverse events of S-1 adjuvant chemotherapy in gastrointestinal cancer patients. Int J Clin Oncol 2016;21(6):1085-90. PubMed

See these in context on the Theanine monograph →

Parts of this content are provided by the Therapeutic Research Center, LLC.

DISCLAIMER: Currently this does not check for drug-drug interactions. This is not an all-inclusive comprehensive list of potential interactions and is for informational purposes only. Not all interactions are known or well-reported in the scientific literature, and new interactions are continually being reported. Input is needed from a qualified healthcare provider including a pharmacist before starting any therapy. Application of clinical judgment is necessary.

© 2021 Therapeutic Research Center, LLC

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